The present invention relates to an ultrasound diagnostic apparatus and an ultrasound image producing method and particularly to an ultrasound diagnostic apparatus that both produces a B mode image and measures a sound speed by transmitting and receiving ultrasonic waves through a transducer array of an ultrasound probe.
Conventionally, ultrasound diagnostic apparatus using ultrasound images are employed in medicine. In general, this type of ultrasound diagnostic apparatus comprises an ultrasound probe having a built-in transducer array and an apparatus body connected to the ultrasound probe. The ultrasound probe transmits an ultrasonic beam toward the inside of a subject's body, receives ultrasonic echoes from the subject, and the apparatus body electrically processes the reception signals to produce an ultrasound image.
In recent years, sound speeds in a region under examination are measured to achieve a more accurate diagnosis of the region inside the subject's body.
JP 2010-99452 A, for example, proposes an ultrasound diagnostic apparatus whereby a plurality of lattice points are set on the periphery of a site under examination and ultrasonic beams are transmitted and received so as to form a transmission focus at the lattice points to obtain reception data, based on which ambient sound speeds and local sound speeds are calculated.